Statues on Salita di Montecavallo, Rome

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Found these seven statues while roaming the Salita (English: Accent/Climb) di Montecavallo, Rome - A path which leads to the famous Piazza del Quirinale - the finest squares of Rome located on the Quirinale Hills, the highest of the seven hills of Rome.

A plaque near the statues indicates that these were installed in 1866, however I couldn't find any information about the identities of the persons in the statues. (View  the contents of the plaque.)

Perhaps some of my readers can give more information about these statues.